Which filament for which purpose? PLA, PETG, ABS, ASA, TPU and nylon compared

The right filament often decides whether a part holds or not. For figures and prototypes, standard PLA is enough. As soon as a part has to withstand heat, sun, impact or constant load, you need a different material. This overview helps you choose and names the typical pitfalls of each filament.

In 30 seconds

• Decoration, figures, prototypes, organizers: PLA. The easiest to print.
• Functional parts and brackets for indoors, containers: PETG.
• Parts in the car, in the sun or outdoors: ASA. ABS if weather does not matter much.
• Soft, elastic parts such as cases, seals, bumpers: TPU.
• Gears, hinges, heavily loaded parts: nylon (PA).
• Especially stiff, light parts: carbon-fibre reinforced variants, with a hardened nozzle.

The overview as a table

All materials at a glance. “Difficulty” says how easily the print succeeds, for price € means cheap and €€€ expensive, each relative to the others. The temperatures are rules of thumb.

Support materials such as PVA and HIPS are not listed here, they usually need a printer with two materials. Prices vary by manufacturer and offer.

The materials at a glance

All temperatures are rules of thumb. The manufacturer's figures on the spool take precedence.

PLA: the uncomplicated standard

• Rules of thumb: nozzle about 190 to 220 °C, bed about 50 to 60 °C. No enclosure needed.
• Strengths: Very easy to print, little warping, clean detail, low odour.
• Weaknesses: Heat resistant only to about 55 °C. A part in a car in the sun can deform. Unsuitable for outdoors and brittle under constant load.
• Choose it for: decoration, models, test fits, organizers, miniatures.

PETG: the all-rounder for functional parts

• Rules of thumb: nozzle about 225 to 250 °C, bed about 70 to 85 °C. No enclosure needed. Keep the part cooling fan moderate, about 20 to 50 percent, because too much cooling weakens layer adhesion. Heat resistant to about 70 to 75 °C.
• Strengths: Tougher and more impact resistant than PLA, good resistance to chemicals and moisture, usable UV resistance.
• Weaknesses: Prone to stringing, see Fix stringing. Absorbs moisture and sometimes sticks too strongly to smooth plates, where a thin coat of glue stick helps as a release agent.
• Choose it for: brackets, housings for indoor electronics, plant pots, hooks.

ABS and ASA: for heat and outdoor use

• Rules of thumb: nozzle about 240 to 260 °C, bed about 95 to 110 °C. An enclosure is mandatory. Heat resistant to about 95 to 100 °C.
• Strengths: Heat resistant, dimensionally stable, strong. ASA is additionally UV and weather resistant and does not fade as ABS does.
• Weaknesses: Prone to heavy warping and cracks, see Prevent warping. Fumes arise while printing, make sure there is ventilation or filtering.
• Choose it for: parts in the car interior, outdoor housings, garden adapters, drone frames.

TPU: for elastic parts

• Rules of thumb: nozzle about 215 to 240 °C, bed about 30 to 60 °C. No enclosure needed. Print very slowly, often 15 to 30 mm/s.
• Strengths: Elastic, wear resistant, dampens vibration. There are different hardnesses, 95A is usual for beginners, 85A and 70A are much softer.
• Weaknesses: Best with a direct drive extruder. In a Bowden system the soft material compresses in the tube, which only works slowly and with patience.
• Choose it for: phone cases, seals, tyres for RC models, furniture bumpers.

Nylon (PA): for load and wear

• Rules of thumb: nozzle about 250 to 280 °C, bed about 90 to 110 °C. An enclosure is recommended. Heat resistance depends strongly on the grade.
• Strengths: Tough, wear resistant, low friction.
• Weaknesses: Nylon absorbs moisture very strongly and must be dried thoroughly before printing. It tends to warp and usually needs an adhesion aid.
• Choose it for: gears, hinges, plain bearings, parts under high load.

Polycarbonate (PC): for extreme loads

• Rules of thumb: nozzle about 270 to 310 °C, bed about 100 to 125 °C. A heated, enclosed chamber is needed.
• Strengths: Very impact resistant and heat resistant, to about 110 to 130 °C.
• Weaknesses: Difficult to print. It needs a hotend that safely withstands these temperatures.
• Choose it for: machine guards and parts with very high requirements.

Fibre-reinforced filaments (for example PETG-CF, PLA-CF, PA-CF)

• Strengths: Added carbon fibres make the part much stiffer, reduce warping and give a matte surface.
• Weaknesses: The fibres are abrasive and wear out a standard brass nozzle in a short time. You need a hardened steel nozzle or one with a ruby tip. The same applies to glass fibre and glow-in-the-dark filaments.
• Choose it for: drone arms, stiff mounting plates, brackets with high stiffness requirements.

Important rules for all materials

• Drying is a must for PETG, TPU and nylon. Wet filament hisses at the nozzle, forms bubbles and gives brittle parts. Store it in a dry box before long prints and follow the manufacturer's drying temperature.
• Check the hotend: Hotends with PTFE lining are usually rated by the manufacturer only to about 240 to 260 °C. With ABS you are at the limit, and for nylon and PC you need a hotend without PTFE in the hot zone.
• Prepare the bed: Textured PEI plates work well for PLA and PETG. With PETG on smooth plates always use a release agent.
• Ventilation: Printing ABS, ASA and nylon produces fumes, print in a well ventilated room.

What does it cost?

The material makes up a large part of the cost of a print, and PLA and PETG are usually the cheapest. What a specific print costs you can work out in the print cost calculator: filament price, weight, power and scrap.

Further reading

• Fix stringing: fine strings, especially with PETG.
• Prevent warping: when corners lift, especially with ABS and ASA.
• Fix layer shifts: when layers slip.
• More tools in the directory

All values are rules of thumb and depend on printer, nozzle and filament. When in doubt, follow your manufacturer's specifications.